Jewel tip capillary pen

ABSTRACT

The disclosure includes several embodiments of a jewel tip for use in pen assemblies mounted on recorder arms of recorder apparatuses. The jewel tip is inserted into the writing end of a capillary pen tip, and, in one embodiment, may have its end protruding to act as the writing tip, or, in another embodiment, may be inset into the capillary pen tip. In either case, the jewel tip serves two purposes, one being to act as a plug to prevent drying of ink in the capillary pen tube and the other being to feed ink to a writing surface at a constant steady rate to assure an uninterrupted line on the writing surface.

United States Patent [1 1 Tullos 1 JEWEL TIP CAPILLARY PEN [76] Inventor: Aubrey R. Tullos, 1510 Haywood St., Odessa, Tex. 79760 [22] Filed: May 15, 1972 [21] Appl. No.: 253,008

[ 51 Nov. 20, 1973 Primary ExaminerJoseph W. Hartary Att0rneyWilliam A. Strauch et al.

[5 7 ABSTRACT The disclosure includes several embodiments of a jewel tip for use in pen assemblies mounted on recorder arms of recorder apparatuses. The jewel tip is inserted into the writing end of a capillary pen tip, and, in one embodiment, may have its end protruding to act as the writing tip, or, in another embodiment, may be inset into the capillary pen tip.

In either case, the jewel tip serves two purposes, one being to act as a plug to prevent drying of ink in the capillary pen tube and the other being to feed ink to a writing surface at a constant steady rate to assure an uninterrupted line on the writing surface.

5 Claims, 7 Drawing Figures JEWEL TIP CAPILLARY PEN CROSS REFERENCE TO RELATED PATENTS Capillary pen systems in and with which the present invention may be used are disclosed in U.S. Pat. No. 3,644,933 issued Feb. 22, 1972 for Reservoir Type Inking Pen Systems and U.S. Pat. No. 3,653,070 issued Mar. 28, 1972 for Nested Sleeve Recording Pen Head.

BACKGROUND OF THE INVENTION The invention is designed for use in a capillary ink feed system for drawing extremely fine, unbroken uniform width lines on stationary or driven charts such as timed movement drum or circular recording charts found in a wide variety of recorder apparatuses. Typically, the pen assembly and the capillary ink feed system include a capillary pen tube connected to an ink supply via a very thin flexible capillary pen tube, and the free end of the pen tube may either having a writing pen tip inserted into a chamber mounted at the pen tube free end, such as is disclosed in the two prior patents mentioned above, or the pen tube free end itself may be drawn to a fine diameter writing point.

This latter structure provides an easily formed, low cost writing tip, but even though such pen tubes with integral writing tips are formed from stainless steel, the writing tips tend to wear rather easily, and ink has a tendency to dry up and clog the fine passageway in the pen tube when not in use.

Problems of writing tip life and ink blockage have been dealt with by various prior art proposals, as exemplified in U. S. Pat. No. 2,600,426, issued June 17, 1952 and in French Pat. No. 1,243,524 granted Sept. 5, 1960. In the U. S. Patent, a jewel tip for a capillary fountain pen is disclosed which imparts a smooth tip and long wear life in such a pen, but no mention is made of the problem or nor is there any teaching of a solution for ink drying and blocking the primary ink passageway. In fact, the interior diameter of the jewel tip is disclosed as being the same as the interior diameter of the remainder of the pen writing point. The French patent overcomes the ink blockage problem by insertion of a writing tip into the usual writing tip end of a pen tube, but the tip disclosed is not a jewel tip. In fact, its teaching is that the inserted tip must be made of sintered metal, polytetrafluoroethylene flock, stacked leaves, or a multichanneled block so that multiple microcapillary passages for ink flow will be provided from the pen tube to the writing tip of the pen.

The present invention provides a jewel tip which may function as a block only, to prevent ink drying within the pen tube, or as a block and writing tip as well. The jewel insert, is made with but a single microcapillary passageway concentric to the pen tube so that uniform ink flow is assured as ink, drying within the pen tube is prevented. 1

SUMMARY OF THE INVENTION A primary object of the invention resides in the provision of a jewel insert having a single microcapillary passageway for a pen tube of a capillary pen system to serve as a plug, to prevent ink drying within the pen tube, and as a flow control means, to assure an uninterrupted, uniform width line on the writing surface contacted by the pen.

Another object of the invention is to provide a jewel insert for capillary pen tube, functioning as a plug and as an ink flow control, the lower end of which may extend from the pen tube as a pen writing tip.

It is a further object of the invention to provide a capillary pen tube jewel insert which may be contoured to a smooth writing tip to produce a fine, even line on the surface being written upon.

Yet another object of the invention to provide a capillary pen tube jewel insert which may be contoured to a smooth writing tip to produce a fine, even line on the surface being written upon.

Further novel features and other objects of this invention will become apparent from the following detailed description, discussion and the appended claims taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS Preferred structural embodiments of this invention are disclosed in the accompanying drawings in which:

FIG. 1 is a partial diagrammatic view illustrating a typical capillary inking pen system of a recorder apparatus;

FIG. 2 is a side elevational view of the recorder arm and pen assembly shown in FIG. 1 with a jewel writing tip insert in the pen tube thereof;

FIG. 3 is a partial elevational view of the pen tube and jewel tip insert as shown in FIG. 2, drawn to an enlarged scale;

FIGS. 4 and 5 are partial sectional views illustrating two embodiments of a jewel insert used as a pen tube plug and writing tip; and

FIGS. 6 and 7 are partial sectional views showing a jewel insert used as a pen tube plug only.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates an inking pen system having an ink supply in the form of a bottle 10 retained on a steel wire hanger 12 by an encircling steel band or clip 14. Bottle 10 is preferably made of resilient plastic and is vertically selectively positionable along the length of hanger 12 to assure proper ink flow. A stopper 16 on bottle 10 supports a vertically oriented stinger 18, inserted through stopper 16 into the bottle 10, and a length of fine diameter flexible plastic capillary tubing 20 serves as a conduit for ink from stinger 18 to end 22 of a pen 24. A bend is formed in pen 24 and 26 to properly vertically orient the writing tip 28 of pen 24 over a circular chart 30. The main body 32 of pen 24 is silver soldered or otherwise suitably secured to recorder arm 34 of a circular chart recorder (not shown) which rotates chart 30 by a timed drive to produce a timed recording in conjunction with sweep movement of recorder arm 34, which is induced by some condition being recorded.

Both stinger 18 and the pen 24 are made of capillary dimension stainless steel tubing, while plastic conduit tubing 20 is made of capillary dimension plastic tubue. In a preferred embodiment, the steel tubing has an CD. on the order 0.0344 inch and an ID. of about 0.023 inch; plastic tubing 20 may be made of *Tygon" plastic with an CD. of 0.059 inch and an ID. of 0.028 inch. In each case, dimensions are not critical.

Referring now to FIGS. 4 through 7, several embodiments of jewel tip inserts are disclosed for the writing tip 28 of pen 24. Jewel insert tip 36 (FIG. 4) is semispherically rounded at 38 to present as smooth a contact point as possible to the paper or chart being recorded.

Jewel insert tip 36 is snugly press fit into writing tip 28 but may be secured in place by anyone of a number of means (e.g., epoxy cement). A single microcapillary passageway 40 is formed concentrically within jewel insert tip 36 to communicate ink from the capillary passageway in pen 24 above jewel insert tip 36 to the paper or chart 30 being recorded. In a preferred embodiment, the diameter of single microcapillary passageway 40 will be on the order of 0.0033 inch 1.

The embodiment illustrated in FIG. is similar to FIG. 4 in that the jewel insert tip 36a is mounted in an extended fashion to serve as a writing tip, but 36a is blunt ended at 42 rather than rounded. The lower circumferential edge 44 of jewel insert tip 36a is slightly rounded to minimize the possibility of marring or tearing the paper or chart being recorded.

The advantages of a jewel insert tip are at least two fold. First, the insert 36 or 36a serves as a plug to prevent air from entering the main capillary passageway of pen 24 which would dry the ink therein and create a block, at least causing ink skipping on the paper or chart 30 or more likely preventing pen 24 from recording at all. Unlike prior art device such as the French Patent No. 1,243,524 discussed above, disclosing an insert having multiple microcapillary passageways to convey ink to the paper, it has been found that but a single microcapillary passageway 40 is sufficient to convey ink to the paper. Additionally, the provision of but a single microcapillary passageway 40 in place of multiple microcapillary passageways, greatly reduces the possibility of air entering the main capillary passageway of pen 24 and creating an ink block.

In the embodiment shown in FIG. 6, a retracted jewel insert tip 46 is disclosed, having a concentric, vertically oriented microcapillary passagewy 40, and is disposed only slightly above writing tip 28 so as to serve as an ink plug very closely adjacent the writing tip 28. Preferably jewel insert tip 46 disposed coincident with a horizontal tangent through the apex of the normal inverse (concave) meniscus of ink which will form at the tip when the pen is not writing. Thus, an annular ring of ink will remain about the junction of jewel insert tip 46 and writing tip 28, but none will be located at the base of microcapillary passageway 40 to possibly create an ink block.

The jewel tip insert 46 illustrated in FIG. 7 is similar in all respects to the insert 46 shown in FIG. 6. In this embodiment, writing tip 28 is drawn into a smaller capillary diameter at its writing end 48. Tip 28 is exteriorally rounded only, at 50 in the embodiment shown in FIG. 6, while the tip 28 is both internally and externally rounded at 52 in the embodiment shown in FIG. 7. In both cases, this finishing treatment provides a very smooth tip which will not rip or tear the paper or chart 30 being recorded.

In each embodiment shown, the jewel has been a ruby primarily because rubies are readily commercially available and inexpensive and have the desired smoothness and hardness qualities suitable for this invention. However, any hard, long wearing, smooth mineral or synthetic material may be used, e.g., sapphire, diamond, glass or carborundum.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to secured by Letters Patent is:

1. In a capillary inking pen system for use with recording apparatus including an ink supply and ink conduit means from the ink supply, an improved writing pen construction comprising: a stainless steel capillary pen tube in fluid communication with the ink conduit means, a pen tip formed on the lower end of said pen tube, ajewel insert spigotted up into the end of said pen tip so that it is disposed entirely within said pen tip, out of contact with a surface being written upon, said jewel insert being disposed so that its lower terminal end is located coincident with the apex of a concave meniscus of ink at the lower end of said pen tip, and means defining a single microcapillary passageway through said jewel insert for communicating ink from the writing pen to a point beneath said jewel insert and above the surface being written upon, whereby said jewel insert acts as a plug to minimize the entrance of air into the main body of the writing pen while providing said single microcapillary passageway, being of sufficient diameter to communicate ink from the writing pen main body to said point above the surface being written upon.

2. The improved writing pen construction as recited in claim 1 wherein said microcapillary passageway is formed vertically within said insert, concentrically with respect to the'side walls of said pen tip.

3. The improved writing pen construction as recited in claim 2 wherein said jewel insert comprises a ruby.

4. The improved writing pen construction as recited in claim 1 wherein said pen tip is drawn into a smaller capillary diameter pen tip end, said jewel insert being located within said smaller capillary diameter end.

5. The improved writing pen construction as recited in claim 1 wherein the diameter of said microcapillary passageway is on the order of 0.0033 inch.

A UNITED STA'IES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,774,231 Dated NOV. 20, 1973 lnv fl Aubrey R. Tullos It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 37, change "or" to --of.

Column 2, line 7, after, "invention insert '-is-- 7 Column 2, line; 57, change "tubue" to tubin g- Column 3, line 1 2, after "but" insert --tip-.

Column 3 line 35, correct the spelling of -passageway-. Column 3,. line 38, after "46" insert --is-. I

Column 3, line 49, "after "end" insert -"-,at--.

Signed and sealed this 9th day of April 197M.

(SEAL) Attest:

EDWARD I'-i.FLETCHER-, JR. C. MARSHALL DANN Attesting Officer- Commissioner of Patents DRM PO-IOSO {10-69) USCOMM'DC 60376-P59 ".5. GOVIINMENT PRINTING OFFICE: I969 O-nifli-JJ UNITED STATES PA'IENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 774, 231 Dated NOV. 20, 1973- Inventor(s) Aubrey R. Tullos It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 37, change "or" to --of--.

Column 2, line 7, after. "invention" insert --is-- Column 2 line: 57, change ftubue" to tubing- Column 3, line l2, after 'but" insert ---t ip-- Column 3 line 35, correct the spelling of --passageway-.

Column 3, line 38, after "46" insert --is--. I I

Column 3, line 49, after "'end" insert --,at---.

Signed and sealed this 9th day of April 197M.

(SEAL) Attest:

EDWARD II-T.FLETCHER,KJR. C. MARSHALL DANN Attesting Officer Commissioner of Patents ORM PC4050 (10-69) USCOMM'DC O37G PG9 0.5. GOVERNMENT PRINHNG OFFICE: (96! O-JG6-3J4 

1. In a capillary inking pen system for use with recording apparatus including an ink supply and ink conduit means from the ink supply, an improved writing pen construction comprising: a stainless steel capillary pen tube in fluid communication with the ink conduit means, a pen tip formed on the lower end of said pen tube, a jewel insErt spigotted up into the end of said pen tip so that it is disposed entirely within said pen tip, out of contact with a surface being written upon, said jewel insert being disposed so that its lower terminal end is located coincident with the apex of a concave meniscus of ink at the lower end of said pen tip, and means defining a single microcapillary passageway through said jewel insert for communicating ink from the writing pen to a point beneath said jewel insert and above the surface being written upon, whereby said jewel insert acts as a plug to minimize the entrance of air into the main body of the writing pen while providing said single microcapillary passageway, being of sufficient diameter to communicate ink from the writing pen main body to said point above the surface being written upon.
 2. The improved writing pen construction as recited in claim 1 wherein said microcapillary passageway is formed vertically within said insert, concentrically with respect to the side walls of said pen tip.
 3. The improved writing pen construction as recited in claim 2 wherein said jewel insert comprises a ruby.
 4. The improved writing pen construction as recited in claim 1 wherein said pen tip is drawn into a smaller capillary diameter pen tip end, said jewel insert being located within said smaller capillary diameter end.
 5. The improved writing pen construction as recited in claim 1 wherein the diameter of said microcapillary passageway is on the order of 0.0033 inch. 